In a DAB (digital audio broadcasting) system, digital radio signals may be transferred in particular for mobile reception in motor vehicles. DRM (Digital Radio Mondial) may provide a digital broadcast transfer system configured for transfer bands below 30 MHz. Transmission parameters may be adjusted with the aid of propagation forecasts, en-route measurements, or listener reports. Regional environmental influences that are of interest in particular for DRM may thereby taken into account. Changes over time may not be sufficiently detected with these methods.
ETSI STC SMG2 UmTS-L1: UTRA Physical Layer Description FDD parts (v0.4, 1998-06-25) Tdoc SMG2 UMTS-L1 221/98 describes, in a mobile radio system, how the base station may adjust its transmission parameters as a function of signals received from mobile radio units. German Published Patent Application No. 198 49 552 describes how transmitted power level of mobile transmit/receive units may be ascertained by the evaluation of received control commands and by a subsequent adaptive calculation in which step intervals that are modifiable in accordance with the control command are adjusted in the context of the transmitted power level control process.
U.S. Pat. No. 6,084,919 describes a configuration made up of a transmitter and a receiver. The receiver, as a function of a spectral analysis, may send feedback to the transmitter which thereupon performs modulation and/or coding.
U.S. Pat. No. 5,511,079 describes a bidirectional satellite broadcast system.
European Patent Application No. 0 848 515 describes a bidirectional radio channel for optimization of a radio link.